Generating API keys on your account could give permission to anyone that has access to the public key, private key or QR code to conduct sensitive actions on your Kraken account. API keys are equivalent to your Kraken username and password.
Kraken’s API Keys are often used to connect a third party service such as a trading bot or a crypto portfolio manager to a Kraken account. These services are thereby entrusted to access the account and could make trades on behalf of the account owner.